JP2023524318A - Synchronization signal block processing method and device, communication device, and readable storage medium - Google Patents

Abstract

The present application discloses a synchronization signal block processing method and apparatus, a communication device and a readable storage medium, the method comprising: detecting a synchronization signal block SSB at a predetermined frequency domain location to obtain a first SSB; One SSB includes the SSB with the target extended cyclic prefix, including at least one of a plurality of identical SSBs, and decoding the first SSB. [Selection drawing] Fig. 5

Description

Cross-reference to related applications

This application is a Chinese Patent Application No. filed in China on May 9, 2020. 202010388668.3, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD The present application belongs to the field of communication, and specifically relates to a method and apparatus for processing synchronization signal blocks, a communication device and a readable storage medium.

Since the propagation loss of the high band is greater than that of the low band, FR2x, ie Beyond 52.6 GHz band, has a shorter coverage distance than Long Time Evolution (LTE). In the process of realizing the present application, the inventors have used beamforming technology in the prior art to expand the coverage of Synchronization Signal Block (SSB). In the access scene, it was found that there was at least the problem that the transmission distance of the SSB signal was short due to the high frequency characteristics, and the SSB coverage was poor.

The purpose of the embodiments of the present application is to provide a synchronization signal block processing method and apparatus capable of solving the problem of short SSB signal transmission distance and poor SSB coverage due to high-frequency characteristics in the initial access scene in the prior art. , to provide a communication device and a readable storage medium.

In order to solve the above technical problems, the present application is realized as follows.

In a first aspect, an embodiment of the present application is detecting a synchronization signal block SSB at a predetermined frequency domain location to obtain a first SSB, said first SSB being an SSB with a target extended cyclic prefix, a plurality of A method for processing synchronization signal blocks is provided, comprising the steps of including at least one of the same SSBs and decoding said first SSB.

In a second aspect, embodiments of the present application include transmitting a first synchronization signal block SSB at a predetermined frequency domain location, said first SSB being an SSB with a target extended cyclic prefix, of a plurality of identical SSBs A method for processing a synchronization signal block including at least one of

In a third aspect, an embodiment of the present application is a detection module for detecting a synchronization signal block SSB at a predetermined frequency domain location to obtain a first SSB, said first SSB being an SSB with a target extended cyclic prefix , a detection module including at least one of a plurality of identical SSBs, and a decoding module for decoding said first SSB.

In a fourth aspect, an embodiment of the present application includes a transmission module for transmitting a first synchronization signal block SSB at a predetermined frequency domain location, said first SSB being an SSB with a target extended cyclic prefix, a plurality of same An apparatus for processing synchronization signal blocks including at least one of SSBs is provided.

In a fifth aspect, embodiments of the present application include a processor, a memory, and a program or instructions stored in said memory and executable on said processor, said program or instructions being executed by said processor to: A communication device is provided that implements the steps of the method described in .

In a sixth aspect, embodiments of the present application include a processor, a memory and a program or instructions stored in said memory and executable on said processor, said program or instructions being executed by said processor; A communication device is provided that implements the steps of the method described in .

In a seventh aspect, embodiments of the present application provide a readable storage medium having stored thereon a program or instructions which, when executed by a processor, implement the steps of the method according to the first aspect.

In an eighth aspect, embodiments of the present application provide a readable storage medium having stored thereon a program or instructions which, when executed by a processor, implement the steps of the method according to the second aspect.

In a ninth aspect, embodiments of the present application include a processor and a communication interface, the communication interface and the processor being coupled, the processor executing a program or instructions to implement the method of the first aspect. provide chips used for

In a tenth aspect, embodiments of the present application include a processor and a communication interface, the communication interface and the processor being coupled, the processor executing a program or instructions to implement the method of the second aspect. provide chips used for

In an embodiment of the present application, a first synchronization signal block SSB can be transmitted at a predetermined frequency domain location, the first SSB including an SSB with a target extended cyclic prefix and at least one of a plurality of identical SSBs. Further, it is also possible to detect the first SSB at a predetermined frequency domain position and decode the detected first SSB. Since the extended cyclic prefix can provide better coverage by suppressing inter-symbol interference and inter-carrier interference due to multipath delay, by transmitting the first SSB with the target cyclic prefix at a predetermined frequency domain location, , the coverage range of the SSB can be further expanded under beamforming, and the first SSB can be detected at a correspondingly farther distance, thus achieving enhanced coverage of the SSB. Also, since multiple identical SSBs are transmitted at a given frequency domain location, there is more than one or more signals from the original, which corresponds to the superposition of multiple powers, i.e., more transmission distance than a single SSB. , and correspondingly the same SSBs can be detected at greater distances, thus achieving enhanced coverage of the SSBs.

FIG. 4 is a structural schematic diagram of an SSB in an embodiment of the present application; FIG. 4 is a schematic diagram of transmitting SSB by beamforming in an embodiment of the present application; 1 is a structural diagram of a network system to which an embodiment of the present application can be applied; FIG. FIG. 1 is a procedure diagram 1 of a method for processing a synchronization signal block according to an embodiment of the present application; FIG. 2 is a flowchart 2 of a method procedure for processing a synchronization signal block according to an embodiment of the present application; FIG. 4 is a schematic diagram of grouping a plurality of synchronous rasters in an embodiment of the present application; FIG. 4 is a schematic diagram of frequency domain repeat transmission of SSB at the same time domain position in an embodiment of the present application; FIG. 4 is a schematic diagram of transmitting or receiving multiple consecutive SSBs in the time domain according to an embodiment of the present application; FIG. 4 is a schematic diagram of transmitting or receiving multiple SSBs at a specific time interval or SSB index interval in an embodiment of the present application; FIG. 4 is a schematic diagram of merging with multiple consecutive SSBs and repeated transmission or reception in the time domain in an embodiment of the present application; FIG. 1 is a structural schematic diagram 1 of a device for processing synchronization signal blocks according to an embodiment of the present application; FIG. 2 is a structural schematic diagram 2 of a device for processing synchronization signal blocks according to an embodiment of the present application; 1 is a structural diagram of a communication device provided in an embodiment of the present application; FIG.

The following clearly and completely describes the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application, and of course the described embodiments are part of the embodiments of the present application. , but not all examples. All other embodiments obtained by persons skilled in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

The terms "first", "second", etc. in the specification and claims of this application are not intended to describe a particular order or order, but to distinguish similar objects. It should be understood that the terms so used may be interchanged with each other where appropriate so that the embodiments of the present application may be performed in orders other than that illustrated or described herein. In addition, "and/or" in the specification and claims means at least one of the connected objects, and the symbol "/" generally means that the related objects before and after are "or" It means that there is a relationship

First, terms related to the present application will be explained.
1) Initial search

The user equipment (User Equipment, UE) needs an initial search at power-on or cell switching, the purpose of which is to obtain cell downlink synchronization by 1) time synchronization detection and 2) frequency synchronization detection. be.

It should be noted that one of the most important functions of the initial search is to find available networks, i.e., the UE should be aware of its supported operating bands and protocol-specified synchronization block numbers. Perform a blind search across all network bands based on the Global Synchronization Channel Number (GSCN). According to the protocol definition, in the FR2 band (24.25G-100GHz), the UE performs a blind search with a step size (sync raster) of 17.28MHz to find a suitable access band for its access.
2) SSB structure

The initial search process is completed by a Synchronization Signal Block (SSB). SSB is a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), a Physical Broadcast Channel (PBCH), and a Demodulation Reference Signal. Signal, DMRS), four consecutive It is composed within Orthogonal Frequency Division Multiplexing (OFDM) symbols and is mainly used for downlink synchronization, and its structure is shown in FIG.
3) SSB transmission mechanism

Due to scarce low-band resources, 5G NR uses high-band such as mmWave, which has a higher propagation loss than low-band, so its coverage distance is shorter than that of LTE. Therefore, in 5G, signal enhancement is achieved by multi-antenna beam forming, and coverage enhancement is achieved, that is, beamforming is used as the SSB transmission method.

Since the beam is narrow, in NR, the same SSB is transmitted in different directions in the form of a beam in the form of a time division duplex (TDD) so that UEs in each direction can receive the SSB. 2, within 5 ms, the base station transmits multiple SSBs (corresponding to different SSB Indexes) to cover different directions respectively. The UE receives multiple SSBs with different signal strengths and selects the SSB with the highest strength as its SSB beam.

In the above example, within a time period of 5 ms, the base station transmits a sequence of SSBs, multiple SSBs in each direction, and this sequence of SSBs is a synchronization signal burst set (SS burst set). The SS burst set repetition period is the SS Burst Set period, which is 20 ms by default in 5G. According to the current standard protocol, the period values of SSB are in the range {ms5, ms10, ms20, ms40, ms80, ms160}. The terminal detects SSB once every 20 ms by default.

The maximum number of SSBs supported within the SS Burst Set is not the same and varies depending on the frequency at which it is located. For F<=6 Ghz, the maximum number of SSBs is 8, and for F>6 Ghz, the maximum number of SSBs is 64. The difference in the maximum number of SSBs is that the higher the frequency, the greater the loss, and the narrower the beam for transmitting SSBs in order to achieve good coverage performance, so it takes more to achieve coverage in each direction. This is because many SSBs are required and therefore the number of SSBs is also large.

SSB Time Domain Positions For a half-frame (5ms) with SSBs, the number of candidate SSBs and the first symbol index positions are determined based on the subcarrier spacing of the SSBs as follows. All of the following cases are for half frames.

- Case A - 15 KHz interval The index of the first symbol of the candidate SSB is {2,8}+14*n. If F(Frequent) <= 3 GHz, then n = 0, 1 (Note: 2 slots are occupied and there are also 2 numbers in { }, in this case there are a total of 4 SSBs at 2 ms, so Lmax=4). For 3 GHz<F<=6 GHz, n=0, 1, 2, 3 (ie 4 slots are occupied and Lmax=8 within 4 ms).

- Case B - 30 KHz interval The index of the 1st symbol of the candidate SSB is {4,8,16,20}+28*n (2 slots are occupied within 1 ms and there are 2 SSBs within 1 slot). For F<=3 GHz, n=0 (ie, Lmax=4 within 1 ms since 2 slots are occupied). For 3 GHz<F<=6 GHz, n=0, 1, 2, 3 (ie 4 slots are occupied and Lmax=8 within 2 ms).

- Case C - 30 KHz interval The index of the 1st symbol of the candidate SSB is {2,8}+14*n (2 slots are occupied within 1 ms and there are 2 SSBs within 1 slot). For F(Frequent)<=3 GHz, n=0, 1 (ie, Lmax=4 within 2 ms, since two slots are occupied). For 3 GHz<F<=6 GHz, n=0, 1, 2, 3 (ie 4 slots are occupied and Lmax=8 within 4 ms).

- Case D - 120 KHz interval The index of the 1st symbol of the candidate SSB is {4, 8, 16, 20} + 28*n, for F > 6 GHz n = 0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18 (8 slots are occupied in 1ms, 2 SSBs in 1 slot, 16 SSBs every 1ms are occupied, for a total of 4 groups, where Lmax=64 within 4 ms).

- Case E - 240 KHz interval The index of the 1st symbol of the candidate SSB is {8, 12, 16, 20, 32, 36, 40, 44} + 56*n, where n = 0, 1, if F > 6 GHz. 2, 3, 5, 6, 7, 8 (16 slots are occupied within 1 ms, 2 SSBs are occupied within 1 slot, 32 SSBs are occupied every 1 ms, a total of 2 groups and in this case, Lmax=64 within 2 ms).
4) Cyclic prefix

One blank symbol can be inserted as a guard interval in Orthogonal Frequency Division Multiplexing (OFDM) systems, which can eliminate Inter Symbol Interference (ISI), but inter-subcarrier interference (Inter Carrier Interference, ICI) cannot be resolved. The cyclic prefix is obtained by extracting the last part of the OFDM signal within a certain length and attaching it to the header of the OFDM signal. and completely eliminate ICI. Cyclic prefixes are divided into regular cyclic prefixes and extended cyclic prefixes, the difference being the different lengths. Higher frequencies generally have smaller cells and delay spreads, and their corresponding CP lengths are shorter.

For a normal cyclic prefix (NCP), a CP is added in each symbol (14 symbols) of one slot, and the CP length is short. For an extended cyclic prefix (ECP), one slot can only transmit 12 symbols, and each symbol has a long CP. ECP can provide better coverage by more effectively suppressing inter-symbol interference, inter-carrier interference due to multipath delay, but system capacity is correspondingly reduced.

Hereinafter, the SSB processing method and the SSB processing apparatus provided in the embodiments of the present application will be described with reference to the drawings, and the SSB processing methods provided in the embodiments of the present application will be described through specific embodiments and their application scenes. and SSB processors are applicable to wireless communication systems. The wireless communication system may be a New Radio (NR) system or other system such as an Evolved Long Term Evolution (eLTE) system or a Long Term Evolution (LTE) system; Alternatively, it may be a future development type communication system or the like. Furthermore, it can be applied to an unlicensed band in the radio communication system.

Please refer to FIG. 3, which is a structural diagram of a network system to which an embodiment of the present application can be applied. As shown in FIG. is User Equipment (UE) or other terminal-side equipment, such as mobile phones, tablet personal computers, laptop computers, personal digital assistants (PDA), mobile Internet It may be a device (Mobile Internet Device, MID), a wearable device (wearable device), or a terminal-side device such as a robot. is. Intermediate devices 12 are devices based on novel artificial metamaterials such as Large Intelligent Surfaces (LIS), backscatter devices, WiFi devices or relay devices (e.g. layer 1 relays, amplifying forwarding relays or transparent forwarding relays, etc.). ) and the like. The network equipment 13 may be a network equipment, a WiFi equipment or a terminal equipment. The network equipment may be a 4G base station, or a 5G base station, or a later version base station, or a base station in other communication systems, or a Node B, an evolved Node B, or a Transmission Reception Point. , TRP), or Access Point (AP), or other terms in the field, as long as the same technical effect can be achieved, the network equipment is not limited to a specific technical term . Also, the network device 13 may be a master node (Master Node, MN) or a secondary node (Secondary Node, SN).

In an embodiment of the present application, terminal 11 may communicate with network device 13 through intermediate device 12, for example, intermediate device 12 may forward signals that terminal 11 transmits to network device 13, and network device 13 may communicate You can also transfer the signals you send. The transfer of the intermediate device 12 may be direct transfer, transparent transfer, amplified transfer, or transmission after converting or modulating the signal frequency, and is not limited to this. Of course, in the embodiments of the present application, the signals transmitted between the terminal 11 and the intermediate equipment 12 may be signals that need to be transmitted between the terminal 11 and the intermediate equipment 12, i.e. the scene is network The device 13 may not be included. Also, the terminal 11 can communicate directly with the network device 13 .

In addition, in the embodiments of the present application, the LIS device is a novel man-made material device, and the LIS node dynamically/semi-statically adjusts its own electromagnetic properties to reflect/refract the electromagnetic wave radiated to the LIS node. Behavior can be affected, eg, the frequency, amplitude, phase, polarization direction, beam spatial energy distribution of the reflected/refracted signal can be changed. The LIS node can control the reflected wave/refracted signal of the electromagnetic signal and realize functions such as beam sweeping/beamforming.

It should be noted that the SSB processing method in the embodiments of the present application involves the interaction between the network side and the terminal side, the equipment on the network side may optionally be a base station or other network equipment, and the The point is that the equipment may alternatively be a UE or other terminal-side equipment.

Based on this, in the embodiments of the present application, the network-side device is the base station, and the terminal-side device is the UE. For the entire interaction process, the steps of the SSB processing method in the embodiments of the present application are:
A step S102 of a base station transmitting a first synchronization signal block SSB at a predetermined frequency domain location, said first SSB comprising an SSB with a target extended cyclic prefix and at least one of a plurality of identical SSBs. a step;
the UE detecting a synchronization signal block SSB at a predetermined frequency domain location to obtain a first SSB step S104;
The UE may include step S106 of decoding said first SSB.

In order to be able to describe the method for processing SSB in the embodiments of the present application in more detail, the steps of the method in the embodiments of the present application are respectively described below from the terminal side and the network side respectively.

For the base station side, please refer to FIG. 4, which is the procedure diagram 1 of the SSB processing method provided in the embodiment of the present application, as shown in FIG. 4, the steps of the method are:
A step S402 of transmitting a first synchronization signal block SSB at a predetermined frequency domain location, the first SSB including an SSB with a target extended cyclic prefix ECP, at least one of a plurality of identical SSBs.

Optionally, the target extended cyclic prefix in embodiments herein may include at least one of extended cyclic prefixes ECP, ECP-1, ECP-2. It should be explained that the above target extended cyclic prefix is only a preferred embodiment of the present application, and other types of target extended cyclic prefixes, such as ECP-3, are also included in the protection scope of the present application, depending on the actual situation. This is a point that can be adjusted.

Since different types of extended cyclic prefixes can all provide better coverage by suppressing inter-symbol interference, inter-carrier interference due to multipath delay, the first SSB with the target cyclic prefix at a given frequency domain location By transmitting , the SSB coverage range can be further expanded under beamforming, and SSB coverage enhancement is realized.

In addition, the first SSB transmitted at a given frequency domain location is a plurality of the same SSBs, and since a plurality of the same SSBs are sent at a given frequency domain location, one or more signals are added to the base station from the beginning. For example, transmitting two identical SSBs together corresponds to superimposing the power of the two, thereby making the coverage distance of the SSBs greater than the transmission distance of a single SSB. , which provides enhanced coverage for SSB.

For the terminal side, please refer to FIG. 5, which is the procedure diagram 2 of the SSB processing method provided in the embodiment of the present application, as shown in FIG. 5, the steps of the method are:
Step S502 of detecting a synchronization signal block SSB at a predetermined frequency domain location to obtain a first SSB, the first SSB comprising an SSB with a target extended cyclic prefix, at least one of a plurality of identical SSBs. and,
and step S504 of decoding the first SSB.

Optionally, the target extended cyclic prefix in embodiments herein may include at least one of extended cyclic prefixes ECP, ECP-1, ECP-2. It should be explained that the above target extended cyclic prefix is only a preferred embodiment of the present application, and other types of target extended cyclic prefixes, such as ECP-3, are also included in the protection scope of the present application, depending on the actual situation. This is a point that can be adjusted.

Different types of extended cyclic prefixes can all provide better coverage by suppressing inter-symbol interference and inter-carrier interference due to multipath delays, so that the target site can be located at a given frequency domain location at a longer coverage distance. A first SSB with a click prefix can be received and enhanced coverage of the SSB is achieved.

In addition, the first SSB that the base station transmits at a given frequency domain location is a plurality of the same SSBs, and since it transmits a plurality of the same SSBs at a given frequency domain location, the base station originally needs one or more signals. increases, e.g., transmitting two identical SSBs together corresponds to superimposing the power of the two, so that the coverage distance of an SSB is compared to the transmission distance of a single SSB. correspondingly, the terminal side can receive the same SSBs at a longer distance, thus realizing enhanced coverage of SSBs.

Optionally, cyclic prefixes of the same SSB in embodiments herein include one of extended cyclic prefix ECP, normal cyclic prefix NCP. The extended cyclic prefix may further include other types of extended cyclic prefixes, such as ECP-1, ECP-2, and so on.

It should be noted that if the first SSB is an SSB with multiple target extended cyclic prefixes or multiple same SSBs, the method for decoding the first SSB in the embodiments of the present application optionally includes: joint decoding may be performed on a plurality of SSBs having .

In other words, when multiple first SSBs are detected, it is necessary to decode the multiple SSBs by joint decoding in order to enhance the coverage of the SSBs.

Optionally, the predetermined frequency-domain locations in embodiments herein are one or more frequency-domain locations in a synchronous raster, or one or more frequency-domain locations in an asynchronous raster, or a combination of synchronous and asynchronous rasters. One or more frequency-domain locations in .

In this regard, in a specific application scenario, when the terminal operates in a specific frequency band (for example, 52.6 GHz), some of the frequency domain locations defined in the frequency band are SSB with extended cyclic prefix structure. used for transmission (1st sync raster set or 3rd non-sync raster set) and another part for SSB transmission with normal cyclic prefix structure (2nd sync raster set or 4th non-sync raster set). be done. The user terminal searches for the SSBs of the target extended cyclic prefix structure in the first sync raster set or the third non-sync raster set, and of course the first sync raster set and the third non-sync raster set are completely orthogonal or overlapping. may have a sync raster that That is, the user can simultaneously search for the SSBs of the target extended cyclic prefix in overlapping sync rasters.

The statement may indicate in the system information or RRC message whether the SSB indicated to be transmitted on this carrier is the normal cyclic prefix structure or the target extended cyclic prefix structure. Also, if multiple SSBs having the target cyclic prefix are detected in the first sync raster set or the third non-sync raster set, joint decoding may be performed on the detected SSBs.

For measuring the RRC message configuration Scell or the system information/RRC message configuration SSB, the user terminal can determine whether the configured SSB is an extended cyclic prefix or normal cyclic prefix structure in at least one of the following ways: .
1) Constructed SSB frequencies, i.e. SSB frequencies and SSBs of the extended cyclic prefix/normal cyclic prefix structure have a correspondence, e.g. reusing the correspondence defined above for the sync raster frequency points However, for non-sync raster frequency points, we define some rules to determine whether it is a target extended cyclic prefix or a normal cyclic prefix.
For example, the frequencies between the sync rasters of two adjacent target extended cyclic prefixes are the target extended cyclic prefixes, the frequencies between the sync rasters of two adjacent normal cyclic prefixes are the normal cyclic prefixes, and the adjacent The frequencies between the sync raster of the normal cyclic prefix and the sync raster of the target extended cyclic prefix are predefined as the target extended cyclic prefix or the normal cyclic prefix.
2) Indicate whether it is the target extended cyclic prefix or the normal cyclic prefix structure that will be used in the frequencies of the indicated configuration SSB.
3) Match the configuration of the target extended cyclic prefix or normal cyclic prefix of the carrier or BWP or specific channel in the configuration cell.

As shown in FIG. 6, assuming that there are originally 10 sync rasters, they may be further divided into two groups of sync rasters, one group carrying the target extended cyclic prefix sequence and another A group carries a normal cyclic prefix sequence, where the target extended cyclic prefix sequence and the normal cyclic prefix sequence may overlap.

Optionally, the predetermined frequency-domain locations in this embodiment are multiple frequency-domain locations corresponding to the same time domain in multiple synchronous rasters and/or asynchronous rasters; A plurality of frequency domain locations in the target time domain, wherein the plurality of periods is a plurality of periods within the plurality of synchronous rasters and/or the asynchronous rasters.

Regarding this, in the specific application scene of the embodiment of the present application, as shown in FIG. , SSB coverage enhancement. That is, the UE can jointly decode SSB1 in sync raster1 with SSB1 in sync raster3 T1 and/or SSB1 in T2. That is, the target time domain is SSB1 at T1 and SSB1 at T2. Of course, the above FIG. 7 is only an example, and the target time domain may be other SSBs, such as SSB3, SSB0, etc., that is, it may be adjusted according to the actual situation, which is not limited in the present application.

For RRC message configuration Scell or measurement of system information/RRC message configuration SSB, the user terminal can determine the frequency domain repeat transmission information of the configured SSB in at least one of the following ways.
1) Configured SSB frequency groups, i.e. SSBs within configured SSB frequency groups, shall be transmitted repeatedly.
2) Configure one SSB frequency and frequency domain repetition times, and the UE derives the SSB frequency according to a predefined rule.

Alternatively, the predetermined frequency-domain location in the embodiments of the present application is the frequency-domain location corresponding to the first set of time-domain locations, and the SSB corresponding to the first set of time-domain locations is the SSB with consecutive indices, the time The interval or SSB index contains at least one of the SSBs satisfying the predetermined relationship.

What should be explained is that SSBs whose time interval or SSB index satisfies a given relationship include continuous SSBs or non-consecutive SSBs whose time interval or SSB index satisfies a given relationship.

In a specific application scene of the embodiments of the present application, it is possible to transmit and receive a plurality of continuous SSBs in the time domain for SSBs with continuous indexes, and further perform joint decoding to enhance coverage of SSBs. can. As shown in FIG. 8, it is predefined or configured by the base station that the quasi-colocation (QCL) information of every R consecutive SSBs is the same. For R=4, the UE can perform merge decoding with SSB 1, 2, 3, 4.

In a specific application scene of the embodiments of the present application, for discontinuous SSBs whose time interval or SSB index satisfies a predetermined relationship, a plurality of SSBs are transmitted and received at a specific time interval or SSB index interval, and joint decoding is performed. can be implemented to achieve enhanced coverage of SSB. There are two methods for discontinuous SSBs whose time interval or SSB index satisfies a predetermined relationship.
1) As shown in FIG. 9, the SSB index is not extended, and SSBs with an SSB index interval of R are defined or configured to be repeatedly transmitted.
2) Perform iterative extension of the SSB pattern.

For larger Subcarrier Spacing (SSB SCS), if FR2 is diverted, one SSB pattern (64 SSBs) is occupied only a fraction of the total 5 ms period, so within the 5 ms period The same SSB pattern can be repeatedly transmitted once or several times to enhance coverage by repetition in the time domain, where additional timing information is required. for example,
In Case A, {4, 8, 16, 20} + 28 * n, and when F > 6 GHz, n = 0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18. This sequence is referred to as sequence 1. After completing the transmission of sequence 1, it is predefined or configured by the base station to continue transmitting sequence 2 after a certain period of time. The time interval may be predefined in the protocol or may be predefined with different values based on the frequency domain location of the sync rater. The Sequence 2 and Sequence 1 are exactly the same, except for the different time domain positions. For example, n=19, 20, 21, 22, 24, 25, 26, 27, 29, 30, 31, 32, 34, 35, 36, 37. It should be noted that the starting value of n may be another value. Joint decoding of multiple SSBs is then performed to enhance the coverage enhancement of the SSBs.
In Case B, {8, 12, 16, 20, 32, 36, 40, 44} + 56 * n, and when F > 6 GHz, n = 0, 1, 2, 3, 5, 6, 7, 8 be. This sequence is referred to as sequence 1. It is pre-defined or configured by the base station to continue transmitting sequence 2 after a certain period of time after completing the transmission of sequence 1 . The time interval may be predefined in the protocol or may be predefined with different values based on the frequency domain location of the sync rater. The Sequence 2 and Sequence 1 are exactly the same, except for the different time domain positions. For example, n=9, 10, 11, 12, 14, 15, 16, 17. It should be noted that the starting value of n may be another value.

In a specific application scene of the embodiments of the present application, for continuous SSBs whose time interval or SSB index satisfies a predetermined relationship, merging of a plurality of continuous SSBs + repeated transmission and reception in the time domain are performed, and joint decoding is performed. Enhanced coverage of SSB can be achieved. As shown in FIG. 10, joint decoding is performed by SSB1 and SSB2 in T1 and SSB1 and SSB2 in T2.

Alternatively, the predetermined relationship in embodiments of the present application may be a predefined predetermined relationship or a predetermined relationship determined based on the frequency domain location of the synchronization raster.

Optionally, the predetermined relationship in embodiments of the present application is
1) the time domain or frequency domain positional relationship between the primary synchronization signal PSS and the secondary synchronization signal SSS;
2) phase difference or cyclic shift between PSS and SSS;
3) a sequence of PSS and/or SSS;
4) phase or cyclic shift of physical broadcast channel--demodulation reference signal PBCH-DMRS;
5) a master system information block MIB or a system information block SIB;
6) radio resource control RRC messages;

What should be discussed is to transmit or receive the SSBs with the target cyclic prefix separately, and to transmit and receive the same SSB in the time domain and/or the frequency domain. The point is that either the SSB with the target cyclic prefix may be repeatedly transmitted and received in the domain, or the SSB with the target cyclic prefix may be repeatedly transmitted and received in the time domain.

It can be seen that in the embodiments of the present application, the network-side device can either transmit an SSB with a target extension prefix at a given frequency domain location, or can transmit multiple identical SSBs. Different types of extended cyclic prefixes can all provide better coverage by suppressing inter-symbol interference, inter-carrier interference due to multipath delays, so that target cyclic prefixes at a given frequency domain location at longer coverage distances The first SSB with the prefix can be received, and accordingly the terminal side can receive the SSB at a longer distance, thus achieving enhanced coverage of the SSB.

Also, transmitting multiple identical SSBs at a given frequency domain location represents an increase of one or more signals from the original to the base station, e.g. It is equivalent to superimposing two powers, which makes the coverage distance of SSB longer than the transmission distance of a single SSB, and accordingly, the terminal side can transmit the same SSB at a longer distance. can be received, which provides enhanced coverage for SSB.

It should be noted that the synchronization signal block processing method provided in the embodiments of the present application is implemented by a synchronization signal block processing device, or the synchronization signal is loaded in the synchronization signal block processing device. It is a point that it may be a control module for executing the processing method to be performed.

Please refer to FIG. 11, which is a structural schematic diagram of a synchronization signal block processing device according to an embodiment of the present application, which is applied to the terminal side. As shown in FIG. 11, the device includes:
A detection module 1102 for detecting a synchronization signal block SSB at a predetermined frequency domain location to obtain a first SSB, the first SSB being an SSB with a target extended cyclic prefix, at least one of a plurality of identical SSBs. a detection module comprising
and a decoding module 1104 for decoding the first SSB.

Optionally, the target extended cyclic prefix in embodiments herein includes at least one of extended cyclic prefixes ECP, ECP-1, ECP-2.

Optionally, the same SSB cyclic prefixes according to embodiments of the present application include one of a target extended cyclic prefix, a normal cyclic prefix.

Optionally, the predetermined frequency-domain locations in embodiments herein are one or more frequency-domain locations in a synchronous raster, or one or more frequency-domain locations in an asynchronous raster, or a combination of synchronous and asynchronous rasters. One or more frequency-domain locations in .

Optionally, the predetermined frequency-domain location in embodiments herein is multiple frequency-domain locations corresponding to the same time-domain in multiple synchronous rasters and/or asynchronous rasters, or the predetermined frequency-domain location is multiple periodic A plurality of frequency-domain locations in the target time domain at , wherein the plurality of periods is a plurality of periods within the plurality of synchronous rasters and/or the asynchronous rasters.

Alternatively, the predetermined frequency-domain location in the embodiments of the present application is the frequency-domain location corresponding to the first set of time-domain locations, and the SSB corresponding to the first set of time-domain locations is the SSB with consecutive indices, the time The interval or SSB index contains at least one of the SSBs satisfying the predetermined relationship.

SSBs whose time intervals or SSB indexes satisfy a predetermined relationship include continuous SSBs or non-successive SSBs whose time intervals or SSB indexes satisfy a predetermined relationship.

Please refer to FIG. 12, which is a structural schematic diagram of a synchronization signal block processing device according to an embodiment of the present application, which is applied to the base station side, as shown in FIG.
A transmitting module 1202 for transmitting a first synchronization signal block SSB at a predetermined frequency domain location, the first SSB including an SSB with a target extended cyclic prefix and at least one of a plurality of identical SSBs.

Optionally, the target extended cyclic prefix in embodiments herein includes at least one of extended cyclic prefixes ECP, ECP-1, ECP-2.

Optionally, the same SSB cyclic prefixes according to embodiments of the present application include one of a target extended cyclic prefix, a normal cyclic prefix.

Optionally, the predetermined frequency-domain locations in embodiments herein are one or more frequency-domain locations in a synchronous raster, or one or more frequency-domain locations in an asynchronous raster, or a combination of synchronous and asynchronous rasters. One or more frequency-domain locations in .

Optionally, the predetermined frequency-domain location in embodiments herein is multiple frequency-domain locations corresponding to the same time-domain in multiple synchronous rasters and/or asynchronous rasters, or the predetermined frequency-domain location is multiple periodic A plurality of frequency-domain locations in the target time domain at , wherein the plurality of periods is a plurality of periods within the plurality of synchronous rasters and/or the asynchronous rasters.

Alternatively, the predetermined frequency-domain location in the embodiments of the present application is the frequency-domain location corresponding to the first set of time-domain locations, and the SSB corresponding to the first set of time-domain locations is the SSB with consecutive indices, the time The interval or SSB index contains at least one of the SSBs satisfying the predetermined relationship. SSBs whose time intervals or SSB indexes satisfy a predetermined relationship include continuous SSBs or non-successive SSBs whose time intervals or SSB indexes satisfy a predetermined relationship.

It should be noted that the synchronization signal processing device applied to the terminal side in the embodiments of the present application may be a device, a component, an integrated circuit or a chip within the terminal. The device may be a mobile communication device or a non-mobile communication device. Illustratively, mobile communication devices include mobile phones, tablet computers, laptops, palmtop computers, vehicle communication devices, wearable devices, ultra-mobile personal computers (UMPCs), netbooks or personal digital assistants (UMPCs). assistant, PDA), etc., and the non-mobile communication device is a server, a network attached storage (NAS), a personal computer (PC), a television (TV), an automated teller machine Alternatively, it may be a kiosk terminal or the like, and is not specifically limited in the embodiments of the present application.

Further, the synchronization signal block processing device in the embodiments of the present application applied to the terminal side in the embodiments of the present application may be a device having an operating system. The operating system may be an Android operating system, an IOS operating system, or other possible operating systems, and is not specifically limited in the embodiments of the present application.

It should be noted that the synchronization signal block processing device applied in the base station side provided in the embodiment of the present application can implement each process in the method embodiment of FIG. Therefore, the description is omitted here.

The synchronization signal block processing device applied to the terminal side provided in the embodiments of the present application can implement each process in the method embodiment of FIG. 5, and the description is omitted here to avoid duplication.

Optionally, embodiments of the present application include processor 1310, memory 1309, and programs or instructions stored in memory 1309 and executable on said processor 1310, said programs or instructions being executed by processor 1310 to: To further provide a communication device that implements each process of the embodiment of the synchronization signal block processing method applied to the base station side or the terminal side, and can achieve technical effects and avoid duplication. Therefore, the explanation is omitted here.

It should be noted that communication devices in the embodiments of the present application include mobile communication devices and non-mobile communication devices as described above.

FIG. 13 is a hardware structural schematic diagram of a communication device that implements an embodiment of the present application.

The communication device 1300 includes components such as a radio frequency unit 1301, a network module 1302, an audio output unit 1303, an input unit 1304, a sensor 1305, a display unit 1306, a user input unit 1307, an interface unit 1308, a memory 1309, and a processor 1310. but not limited to them.

Those skilled in the art will appreciate that the communication device 1300 may further include a power source (e.g., a battery) for powering each component, the power source being logically connected to the processor 1310 by a power management system and further charged and discharged by the power management system. It can be appreciated that functions such as management and power consumption management can be implemented. The communication device structure shown in FIG. 13 is not intended to limit the communication device, and the communication device may include more or fewer members than shown, or a combination of some members, or a different arrangement of members, and the description is omitted here. do.

When the communication device is a terminal-side communication device, the radio frequency unit 1301 is used to detect a synchronization signal block SSB at a predetermined frequency domain position to obtain a first SSB, the first SSB being a target extension An SSB with a cyclic prefix, including at least one of a plurality of identical SSBs.

A processor 1310 is used to decode the first SSB.

When the communication device is a base station side communication device, the radio frequency unit 1301 is used to transmit a first synchronization signal block SSB at a predetermined frequency domain location, and the first SSB is a target extended cyclic An SSB with prefix ECP, including at least one of a plurality of identical SSBs.

Optionally, said target extended cyclic prefix comprises at least one of extended cyclic prefixes ECP, ECP-1, ECP-2.

Optionally, the cyclic prefixes of said plurality of same SSBs comprise one of extended cyclic prefix ECP, normal cyclic prefix NCP.

Optionally, said predetermined frequency-domain locations are one or more frequency-domain locations in a synchronous raster, or one or more frequency-domain locations in an asynchronous raster, or one or more in a combination of synchronous and asynchronous rasters. A plurality of frequency domain locations.

Optionally, said predetermined frequency-domain locations are multiple frequency-domain locations corresponding to the same time-domain in multiple synchronous rasters and/or asynchronous rasters, or predetermined frequency-domain locations are target time-domain locations in multiple cycles. and the multiple periods are multiple periods in the multiple synchronous rasters and/or the multiple asynchronous rasters.

Optionally, the predetermined frequency-domain locations are frequency-domain locations corresponding to a first set of time-domain locations, and the SSBs corresponding to the first set of time-domain locations are consecutive SSBs, time intervals, or SSBs. The index contains at least one of the SSBs satisfying the predetermined relationship. The SSBs whose time interval or SSB index satisfies a predetermined relationship include continuous SSBs or non-successive SSBs whose time interval or SSB index satisfy a predetermined relationship.

Optionally, said predetermined relation is a predefined predetermined relation or a predetermined relation determined based on the frequency domain position of the synchronization raster.

Optionally, the predetermined relationship is a time domain or frequency domain positional relationship between the primary synchronization signal PSS and the secondary synchronization signal SSS, a phase difference or cyclic shift between PSS and SSS, and a sequence of PSS and/or SSS. , a phase or cyclic shift of the physical broadcast channel--demodulation reference signal PBCH-DMRS, a master system information block MIB or system information block SIB, and a radio resource control RRC message.

Embodiments of the present application further provide a readable storage medium storing a program or instructions that, when executed by a processor, implement each process of the above embodiments of the method for processing synchronization signal blocks, and technical effects and is omitted here to avoid duplication.

The processor is the processor in the communication device described in the above embodiments. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and the like.

An embodiment of the present application includes a processor and a communication interface, the communication interface and the processor are combined, and the processor executes a program or instructions to implement each process of the embodiment of the method for processing the synchronization signal block. In order to further provide the chip used for and achieve the technical effect, and to avoid duplication, the description is omitted here.

It should be understood that the chips referred to in the embodiments of the present application may also be referred to as system level chips, system chips, chip systems, system-on-chip, or the like.

It can be appreciated that the embodiments described in this disclosure can be implemented in hardware, software, firmware, middleware, microcode, or a combination thereof. For a hardware implementation, modules, units, sub-modules, sub-units, etc., are defined as one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), digital signal Processing Unit (DSP Device, DSPD), Programmable Logic Device (PLD), Field-Programmable Gate Array (FPGA), Common Processor, Controller, Microcontroller, Microprocessor, Functions described in the present application can be implemented in other electronic units or combinations thereof for performing

It should be noted that, as used herein, the terms “comprising,” “consisting of,” or any other variation are intended to include non-exclusive inclusion, whereby a process, method, article comprising a series of elements or apparatus may include those elements as well as other elements not specified or specific to such process, method, article, or apparatus. Unless specifically stated otherwise, an element limited by the phrase "comprising a" does not exclude the presence of additional identical elements in the process, method, article or apparatus containing the element. It should also be pointed out that the scope of the methods and apparatus in the embodiments herein is not limited to performing the functions in the order illustrated or discussed, but rather that functions may be performed substantially concurrently or in reverse order depending on such functions. For example, methods described may be performed in a different order than described, and steps may be added, omitted, or combined. Also, features described with reference to any example may be combined in other examples.

From the description of the above embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented in the form of a combination of software and the necessary common hardware platform. may be used, although the former is often the preferred embodiment. Based on this observation, the technical solution of the present application can be implemented in the form of a software product substantially or the part that contributes to the prior art, and the computer software product includes a storage medium (such as ROM/ RAM, magnetic disk, optical disk) and includes a plurality of instructions that cause a terminal (which may be a mobile phone, computer, server, air conditioner, network device, etc.) to perform the method described in each embodiment of the present application. .

Although the embodiments of the present application have been described above with reference to the drawings, the present application is not limited to the above specific embodiments, and the above specific embodiments are merely exemplary and restrictive. Instead, many forms that a person skilled in the art can make based on the suggestions of the present application without departing from the spirit of the present application and the scope of protection of the claims shall belong to the protection scope of the present application.

Claims (38)

Detecting a synchronization signal block SSB at a predetermined frequency domain location to obtain a first SSB, said first SSB comprising an SSB with a target extended cyclic prefix, at least one of a plurality of identical SSBs. and,
decoding said first SSB. The method of claim 1, wherein the target extended cyclic prefix includes at least one of extended cyclic prefixes ECP, ECP-1, ECP-2. 2. The method of claim 1, wherein the plurality of same SSB cyclic prefixes comprise one of a target extended cyclic prefix, a normal cyclic prefix. The predetermined frequency-domain locations are one or more frequency-domain locations in a synchronous raster, or one or more frequency-domain locations in an asynchronous raster, or one or more frequency-domain locations in a combination of synchronous and asynchronous rasters. 2. The method of claim 1, wherein the position. the predetermined frequency domain locations are multiple frequency domain locations corresponding to the same time domain in multiple synchronous rasters and/or asynchronous rasters; or
3. The predetermined frequency domain positions are a plurality of frequency domain positions in the target time domain in a plurality of periods, the plurality of periods being a plurality of periods within a plurality of synchronous rasters and/or a plurality of asynchronous rasters. 4. The method described in 4. the predetermined frequency-domain location is a frequency-domain location corresponding to a first set of time-domain locations;
The method according to claim 1 or 4, wherein the SSBs corresponding to the first set of time-domain locations include at least one of SSBs with consecutive indices, SSBs with time intervals or SSB indices satisfying a predetermined relationship. 7. The method of claim 6, wherein the SSBs whose time intervals or SSB indices satisfy a predetermined relationship include continuous SSBs or non-consecutive SSBs whose time intervals or SSB indices satisfy a predetermined relationship. 7. The method of claim 6, wherein the predetermined relationship is a predefined predetermined relationship or a predetermined relationship determined based on frequency domain locations of synchronization rasters. The predetermined relationship is
a time-domain or frequency-domain positional relationship between the primary synchronization signal PSS and the secondary synchronization signal SSS;
a phase difference or cyclic shift between PSS and SSS;
a sequence of PSS and/or SSS;
physical broadcast channel--phase or cyclic shift of demodulation reference signal PBCH-DMRS;
a master system information block MIB or a system information block SIB;
7. The method of claim 6, comprising at least one of: a Radio Resource Control RRC message. The step of decoding the first SSB comprises:
2. The method of claim 1, comprising performing joint decoding on multiple SSBs with a target cyclic prefix or multiple identical SSBs. transmitting a first synchronization signal block SSB at a predetermined frequency domain location, said first SSB comprising an SSB having a target extended cyclic prefix ECP, at least one of a plurality of identical SSBs. How to handle. 12. The method of claim 11, wherein the target extended cyclic prefix comprises at least one of extended cyclic prefixes ECP, ECP-1, ECP-2. 12. The method of claim 11, wherein the plurality of same SSB cyclic prefixes comprise one of a target extended cyclic prefix, a normal cyclic prefix. The predetermined frequency-domain locations are one or more frequency-domain locations in a synchronous raster, or one or more frequency-domain locations in an asynchronous raster, or one or more frequency-domain locations in a combination of synchronous and asynchronous rasters. 12. The method of claim 11, wherein the position. the predetermined frequency domain locations are multiple frequency domain locations corresponding to the same time domain in multiple synchronous rasters and/or asynchronous rasters; or
12. The predetermined frequency domain positions are a plurality of frequency domain positions in the target time domain in a plurality of periods, the plurality of periods being a plurality of periods within a plurality of synchronous rasters and/or a plurality of asynchronous rasters. 14. The method according to 14. the predetermined frequency-domain location is a frequency-domain location corresponding to a first set of time-domain locations;
15. The method according to claim 11 or 14, wherein the SSBs corresponding to the first set of time-domain locations include at least one of SSBs with consecutive indices, SSBs whose time intervals or SSB indices satisfy a predetermined relationship. 17. The method of claim 16, wherein the SSBs whose time intervals or SSB indices satisfy a predetermined relationship include continuous SSBs or non-consecutive SSBs whose time intervals or SSB indices satisfy a predetermined relationship. 17. The method of claim 16, wherein the predetermined relationship is a predefined predetermined relationship or a predetermined relationship determined based on frequency domain locations of synchronization rasters. The predetermined relationship is
a time-domain or frequency-domain positional relationship between the primary synchronization signal PSS and the secondary synchronization signal SSS;
a phase difference or cyclic shift between PSS and SSS;
a sequence of PSS and/or SSS;
physical broadcast channel--phase or cyclic shift of demodulation reference signal PBCH-DMRS;
a master system information block MIB or a system information block SIB;
19. The method of claim 18, comprising at least one of: a Radio Resource Control RRC message. A detection module for detecting a synchronization signal block SSB at a predetermined frequency domain location to obtain a first SSB, said first SSB being an SSB with a target extended cyclic prefix, at least one of a plurality of identical SSBs. a detection module comprising
a decoding module for decoding said first SSB. 21. The apparatus of claim 20, wherein the target extended cyclic prefix includes at least one of extended cyclic prefixes ECP, ECP-1, ECP-2. The predetermined frequency-domain locations are one or more frequency-domain locations in a synchronous raster, or one or more frequency-domain locations in an asynchronous raster, or one or more frequency-domain locations in a combination of synchronous and asynchronous rasters. 21. The device of claim 20, wherein the position. the predetermined frequency domain locations are multiple frequency domain locations corresponding to the same time domain in multiple synchronous rasters and/or asynchronous rasters; or
21. or wherein said predetermined frequency domain positions are a plurality of frequency domain positions in a target time domain in a plurality of periods, said plurality of periods being a plurality of periods within a plurality of synchronous rasters and/or a plurality of asynchronous rasters. 23. The device according to 22. the predetermined frequency-domain location is a frequency-domain location corresponding to a first set of time-domain locations;
23. The apparatus according to claim 20 or 22, wherein the SSBs corresponding to the first time-domain location set include at least one of SSBs with consecutive indices, SSBs with time intervals or SSB indices satisfying a predetermined relationship. 25. The apparatus of claim 24, wherein the SSBs whose time intervals or SSB indices satisfy a predetermined relationship include continuous SSBs or non-consecutive SSBs whose time intervals or SSB indices satisfy a predetermined relationship. a transmitting module for transmitting a first synchronization signal block SSB at a predetermined frequency domain location, said first SSB including an SSB with a target extended cyclic prefix ECP, at least one of a plurality of identical SSBs; Synchronization signal block processor. 27. The apparatus of claim 26, wherein the target extended cyclic prefix includes at least one of extended cyclic prefixes ECP, ECP-1, ECP-2. The predetermined frequency-domain locations are one or more frequency-domain locations in a synchronous raster, or one or more frequency-domain locations in an asynchronous raster, or one or more frequency-domain locations in a combination of synchronous and asynchronous rasters. 27. The device of claim 26, wherein the position. the predetermined frequency domain locations are multiple frequency domain locations corresponding to the same time domain in multiple synchronous rasters and/or asynchronous rasters; or
27 or, wherein said predetermined frequency domain positions are a plurality of frequency domain positions in a target time domain in a plurality of periods, said plurality of periods being a plurality of periods within a plurality of synchronous rasters and/or a plurality of asynchronous rasters; 28. The apparatus according to 28. the predetermined frequency-domain location is a frequency-domain location corresponding to a first set of time-domain locations;
29. The apparatus according to claim 26 or 28, wherein the SSBs corresponding to the first set of time-domain locations include at least one of SSBs whose indices are consecutive, SSBs whose time intervals or SSB indices satisfy a predetermined relationship. 31. The apparatus of claim 30, wherein the SSBs whose time intervals or SSB indices satisfy a predetermined relationship include contiguous SSBs or non-contiguous SSBs whose time intervals or SSB indices satisfy a predetermined relation. Synchronization according to any one of claims 1 to 10, comprising a processor, a memory and a program or instructions stored in said memory and executable on said processor, said program or instructions being executed by said processor. A communication device that implements the steps of the signal block processing method. Synchronization according to any one of claims 11 to 19, comprising a processor, a memory and a program or instructions stored in said memory and executable on said processor, said program or instructions being executed by said processor. A communication device that implements the steps of the signal block processing method. A readable storage medium storing a program or instructions which, when executed by a processor, implements the steps of the method for processing synchronization signal blocks according to any one of claims 1 to 10. A readable storage medium storing a program or instructions which, when executed by a processor, implements the steps of the method for processing synchronization signal blocks according to any one of claims 11 to 19. comprising a processor and a communication interface, the communication interface and the processor being coupled, the processor executing a program or instructions to perform the steps of the method for processing synchronization signal blocks according to any one of claims 1 to 10 or used to implement the steps of the method for processing synchronization signal blocks according to any one of claims 11 to 19. When executed by at least one processor, it implements the steps of the method for processing synchronization signal blocks according to any one of claims 1 to 10, or according to any one of claims 11 to 19. A computer program product that implements the steps of the synchronization signal block processing method. configured to perform the steps of the method for processing synchronization signal blocks according to any one of claims 1 to 10 or the steps of the method for processing synchronization signal blocks according to any one of claims 11 to 19. communication equipment.

Images